<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        html,body{
            height: 100%;
        }
        body{
            margin: 0;
            /* display: flex;
            justify-content: center;
            align-items: center; */
        }
        .row{
            display: flex;
            justify-content: center;
        }
        .col{
            /* width: 300px; */
            flex: 1;    /* 等分 */
            height: 200px;
            background-color: pink;
            text-align: center;
            line-height: 200px;
        }
        .ljr{
            background-color: green;
        }
        .col:nth-child(2n){
            background-color: green;
        }
        .container{
            width: 1200px;
            margin: 0 auto;
        }
        @media screen and (max-width:480px){
            .container{
                width: 100%;
            }
            .row{
                overflow: hidden;
                flex-wrap: wrap;
            }
            .col{
                flex: none;
                width: 50%;
            }
        }
    </style>
</head>
<body>
    <div class="container">
    <div class="row">
        <div class="col">1</div>
        <div class="col">2</div>
        <div class="col">3</div>
        <div class="col">4</div>
    </div>
</div>
    <script src="./js/app.js"></script>
    <script src="https://cdn.bootcdn.net/ajax/libs/three.js/r128/three.min.js"></script>
</body>
</html>